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#include "AdunKernel/AdunBerendsenThermostat.h"
@implementation AdBerendsenThermostat
- (id) init
{
return [self initWithTargetTemperature: 300.0
couplingFactor: 100.0];
}
- (id) initWithTargetTemperature: (double) doubleOne
couplingFactor: (double) doubleTwo
{
if((self = [super init]))
{
[self setTargetTemperature: doubleOne];
couplingFactor = doubleTwo;
timeStep = 1;
timePerCouplingFactor = (double)timeStep/couplingFactor;
}
return self;
}
- (NSString*) description
{
NSMutableString* description = [NSMutableString string];
[description appendFormat: @"%@. Target temperature %5.2lf. Coupling factor %5.2lf",
NSStringFromClass([self class]), targetTemperature, couplingFactor];
return description;
}
- (void) simulator: (AdSimulator*) aSimulator
willBeginProductionWithSystems: (AdSystemCollection*) aSystemCollection
forceFields: (AdForceFieldCollection*) aForceFieldCollection
{
timeStep = [aSimulator timeStep];
timePerCouplingFactor = (double)timeStep/couplingFactor;
}
- (void) simulatorDidPerformSecondVelocityUpdateForSystem: (AdSystem*) system
{
int j,k;
double temperature, factor;
AdMatrix* velocities;
temperature = [system temperature];
if(temperature == 0)
{
factor = 0;
}
else
{
factor = 1 - timePerCouplingFactor*(1 - (targetTemperature/temperature));
factor = sqrt(factor);
}
velocities = [system velocities];
[system object: self willBeginWritingToMatrix: velocities];
for(j=0; j < velocities->no_rows; j++)
for(k=0; k<3; k++)
velocities->matrix[j][k] *= factor;
[system object: self didFinishWritingToMatrix: velocities];
}
- (void) setTargetTemperature: (double) aDouble
{
if(aDouble < 0)
[NSException raise: NSInvalidArgumentException
format: @"Temperature cannot be less than 0"];
targetTemperature = aDouble;
}
- (double) targetTemperature
{
return targetTemperature;
}
- (void) setCouplingFactor: (double) aDouble
{
couplingFactor = aDouble;
timePerCouplingFactor = (double)timeStep/couplingFactor;
}
- (double) couplingFactor
{
return couplingFactor;
}
- (void) simulatorWillPerformFirstVelocityUpdateForSystem: (AdSystem*) aSystem
{
//Does nothing here
}
- (void) simulatorWillPerformPositionUpdateForSystem: (AdSystem*) aSystem
{
//Does nothing here
}
- (void) simulatorDidPerformPositionUpdateForSystem: (AdSystem*) aSystem
{
//Does nothing here
}
- (void) simulatorWillPerformSecondVelocityUpdateForSystem: (AdSystem*) aSystem
{
//Does nothing here
}
- (void) simulatorDidFinishProduction: (AdSimulator*) aSimulator
{
//Does nothing here
}
@end
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